Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly fo...Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly formation of a trivalent G-quadruplex/hemin DNAzyme for colorimetric detection of Hg^(2+).A hairpin DNA(Hr)was designed with thymine-Hg^(2+)-thymine pairs that catalyzed by Exo III is prompted to happen upon binding Hg^(2+).A released DNA fragment triggers the catalytic assembly of other three hairpins(H1,H2,and H3)to form many trivalent G-quadruplex/hemin DNA enzymes for signal output.The developed sensor shows a dynamic range from 2 pM to 2μM,with an impressively low detection limit of 0.32 pM for Hg^(2+)detection.Such a sensor also has good selectivity toward Hg^(2+)detection in the presence of other common metal ions.This strategy shows the great potential for visual detection with portable type.展开更多
AIM: To evaluate the inhibitory effects of DNAzymes on the expressions of hepatitis B virus (HBV) s (HBsAg) and e (HBeAg) in 2.2.15 cells, and to explore the potential therapeutic effects of DNAzymes on replication of...AIM: To evaluate the inhibitory effects of DNAzymes on the expressions of hepatitis B virus (HBV) s (HBsAg) and e (HBeAg) in 2.2.15 cells, and to explore the potential therapeutic effects of DNAzymes on replication of HBV genome. METHODS: DNAzymes DrzBS and DrzBC specific to HBV (aywsubtype) s gene ORF A^157UG and e gene ORF A^1816UG, were designed and synthesized. Inhibitory effects of DrzBS or DrzBC on the expressions of HBV s and e genes as well as HBV DNA levels in culture supernatants were observed in 2.2.15 cells. RESULTS: After being treated with DrzBS or DrzBC, the expression of HBV s or e genes in 2.2.15 cells was depressed dramatically. The maximum inhibition rate was 94.2% and 91.8% for DrzBS and DrzBC, respectively. The concentration for effective inhibition of both DrzBS and DrzBC was within 0.1-2.5 μmol/L, showing a dosedependence. The efficiency of inhibiting HBsAg, HBeAg in 2.2.15 cells by DrzBS or DrzBC was higher than that of the same target genes by antisense oligonucleotides (ASON). The concentration for effective inhibition of DNAzymes was at least 10-fold lower compared with ASON controls. Neither inhibition on the replication of HBV DNA nor toxicity to 2.2.15 cells was observed. CONCLUSION: DrzBS and DrzBC can block the expression of HBV s- and e-genes in 2.2.15 cells and provide a specific and effective anti-HBV gene therapeutic means.展开更多
To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined...To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined their inhibitory capabilities of the ampicillin-resistance of TEM-1 and TEM-3 bacteria. Dz1 was a traditional 10-23 DNAzyme, Dz2 was the mutant of Dz1 by addition of the protected nucleotide to each ann of the enzyme, and Dz3 was a mutant of Dz1 at antisense arms of which phosphorothioate modifications were made. Kinetic analysis, bacterial growth, and β-lactamase activity measurement showed that all the three DNAzymes worked efficiently in vitro and in vivo. A 9 hours bacterial growth inhibition test showed that the inhibition rates of TEM-1 bacteria by Dz1, Dz2, and Dz3 were 27%, 50%, and 29%, respectively. In addition, the inhibition rates of TEM-3 bacteria by those three DNAzymes were found io be 49%, 58%, and 45%, respectively. The current findings suggest that DNAzymes may become potential candidates of alternative inhibitors for bacteria drug-resistance.展开更多
Detection of deoxyribozyme （DNAzyme） cleavage process usually needs complex and time-consuming radial labeling, gel electrophoresis and autoradiography. This paper reported an approach to detect DNAzyme cleavage pro...Detection of deoxyribozyme （DNAzyme） cleavage process usually needs complex and time-consuming radial labeling, gel electrophoresis and autoradiography. This paper reported an approach to detect DNAzyme cleavage process in real time using a fluorescence probe. The probe was employed as DNAzyme substrate to convert directly the cleavage information into fluorescence signal in real time. Compared with traditional approach, this non-isotope method not only brought a convenient means to monitor the DNAzyme cleavage reaction, but also offered abundant dynamic data for choosing potential gene therapeutic agents. It provides a new tool for DNAzyme research, as well as a new insight into research on human disease diagnosis. Based on this method, 8- 17deoxyribozyme （8-17DNAzyme） against hepatitis C virus RNA （HCV-RNA） was designed and the cleavage process was studied in real time. ？2009 Ke Min Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.展开更多
金属离子几乎参与所有生命过程,它们的亚细胞定位与许多生物功能密切相关。亚细胞金属离子的扰动可导致细胞功能受损,并增加代谢相关疾病的风险。最近中国科学院国家纳米科学中心的李乐乐教授基于DNAzyme传感器构建了线粒体中金属离子...金属离子几乎参与所有生命过程,它们的亚细胞定位与许多生物功能密切相关。亚细胞金属离子的扰动可导致细胞功能受损,并增加代谢相关疾病的风险。最近中国科学院国家纳米科学中心的李乐乐教授基于DNAzyme传感器构建了线粒体中金属离子空间选择性成像的模块化工程,这一成果发表在Journal of The American Chemical Society上。展开更多
DNAzyme-based gene therapy faces some challenges including cell penetration,activity limitation,and co-delivery functions.Self-assembled DNA nanomedicine has attracted widespread attention due to its many advantages.I...DNAzyme-based gene therapy faces some challenges including cell penetration,activity limitation,and co-delivery functions.Self-assembled DNA nanomedicine has attracted widespread attention due to its many advantages.It is urgent to develop a universal DNA degradation strategy for precise programmable drug release.Herein,we reported a self-catabolic DNAzyme nanospheres(SCNS),which could simultaneously achieve cell penetration,activity enhancement,and co-delivery functions.The SCNS were assembled through Y-DNA stepwise hybridization with each other,which were then loaded with aptamer(Apt),doxorubicin(Dox),and zinc oxide nanoparticles(ZnO NPs).The acid-triggered dissociation of ZnO NPs leads to the generation of Zn^(2+)ions cofactors for immediately self-catabolic DNAzyme nanospheres.After the disassembly of the SCNS,three types of anticancer treatments would be activated,which include Zn^(2+)involved reactive oxygen species(ROS),Dox-induced chemotherapy,and DNAzyme-based gene therapy.The experimental results show that the nanoplatform(Apt-SCNS-Dox-ZnO)has a good tumor-killing effect and minimal side effects.As a smart self-driven drug delivery nanoplatform,it is anticipated to displace extraordinary potential in biomedicine and bioengineering.展开更多
Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale dimensions.Intelligent DNA machines and netw...Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale dimensions.Intelligent DNA machines and networks have been widely used in various fields,including molecular imaging,biosensors,drug delivery,information processing,and logic operations.Encoders serve as crucial components for information compilation and transfer,allowing the conversion of information from diverse application scenarios into a format recognized and applied by DNA circuits.However,there are only a few encoder designs with DNA outputs.Moreover,the molecular priority encoder is hardly designed.In this study,we introduce allosteric DNAzyme-based encoders for information transfer.The design of the allosteric domain and the recognition arm allows the input and output to be independent of each other and freely programmable.The pre-packaged mode design achieves uniformity of baseline dynamics and dynamics controllability.We also integrated non-nucleic acid molecules into the encoder through the aptamer design of the allosteric domain.Furthermore,we developed the 2^(n)-n encoder and the EndoⅣ-assisted priority encoder inspired by immunoglobulin's molecular structure and effector patterns.To our knowledge,the proposed encoder is the first enzyme-free DNA encoder with DNA output,and the priority encoder is the first molecular priority encoder in the DNA reaction network.Our encoders avoid complex operations on a single molecule,and their simple structure facilitates their application in complex DNA circuits and biological scenarios.展开更多
基金Supported by The Science and Technology Project of General Administration of Quality Supervision,Inspection and Quarantine (2015IK126)The Science and Technology Project of Changsha City of Hunan Province of China (KQ1602124).
文摘Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly formation of a trivalent G-quadruplex/hemin DNAzyme for colorimetric detection of Hg^(2+).A hairpin DNA(Hr)was designed with thymine-Hg^(2+)-thymine pairs that catalyzed by Exo III is prompted to happen upon binding Hg^(2+).A released DNA fragment triggers the catalytic assembly of other three hairpins(H1,H2,and H3)to form many trivalent G-quadruplex/hemin DNA enzymes for signal output.The developed sensor shows a dynamic range from 2 pM to 2μM,with an impressively low detection limit of 0.32 pM for Hg^(2+)detection.Such a sensor also has good selectivity toward Hg^(2+)detection in the presence of other common metal ions.This strategy shows the great potential for visual detection with portable type.
基金Supported by the National Natural Science Foundation of China,No.30271183
文摘AIM: To evaluate the inhibitory effects of DNAzymes on the expressions of hepatitis B virus (HBV) s (HBsAg) and e (HBeAg) in 2.2.15 cells, and to explore the potential therapeutic effects of DNAzymes on replication of HBV genome. METHODS: DNAzymes DrzBS and DrzBC specific to HBV (aywsubtype) s gene ORF A^157UG and e gene ORF A^1816UG, were designed and synthesized. Inhibitory effects of DrzBS or DrzBC on the expressions of HBV s and e genes as well as HBV DNA levels in culture supernatants were observed in 2.2.15 cells. RESULTS: After being treated with DrzBS or DrzBC, the expression of HBV s or e genes in 2.2.15 cells was depressed dramatically. The maximum inhibition rate was 94.2% and 91.8% for DrzBS and DrzBC, respectively. The concentration for effective inhibition of both DrzBS and DrzBC was within 0.1-2.5 μmol/L, showing a dosedependence. The efficiency of inhibiting HBsAg, HBeAg in 2.2.15 cells by DrzBS or DrzBC was higher than that of the same target genes by antisense oligonucleotides (ASON). The concentration for effective inhibition of DNAzymes was at least 10-fold lower compared with ASON controls. Neither inhibition on the replication of HBV DNA nor toxicity to 2.2.15 cells was observed. CONCLUSION: DrzBS and DrzBC can block the expression of HBV s- and e-genes in 2.2.15 cells and provide a specific and effective anti-HBV gene therapeutic means.
文摘目的分析肿瘤远处转移相关蛋白(Ezrin mRNA)的结构,寻找并验证DNAzymes作用的最佳靶点。方法利用RNAstructure与RNAdraw程序分析Ezrin mRNA结构,计算其一、二级结构,两种程序同时计算出碱基未配对的单链成环区,且连续存在4个以上,则将其设为反义技术的靶区域,在此区域内设计DNAzymes的作用靶点,再依据最低自由能原则,运用计算机中的OligoWalk程序进行筛选,以此方式得到各反义技术的作用靶点,以实验方法验证预测结果。结果两种软件预测的共同的单链区共42个,其中完全匹配的单链区21个,编码区具27个。AU1655、AU1751、AU1766、AU1789及GU2623位于连续未配对碱基超过10个的单链区,仅AU1655、AU1751、AU1766、AU1789符合要求。酶切反应结果显示DNAzymes在AU1751位点能够最为理想地切割Ezrin m RNA。结论相对于传统的单纯依靠实验来寻找靶点,核酸二级结构联合热动力学参数能够更精确、快速地处理靶点的设计和选取问题。AU1751位点相对应的DNAzymes不易形成稳定的自身杂合体,有利于DNAzymes结合RNA。
基金the National Natural Science Foundation of China(Nos.20771030 and 20671025)
文摘To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined their inhibitory capabilities of the ampicillin-resistance of TEM-1 and TEM-3 bacteria. Dz1 was a traditional 10-23 DNAzyme, Dz2 was the mutant of Dz1 by addition of the protected nucleotide to each ann of the enzyme, and Dz3 was a mutant of Dz1 at antisense arms of which phosphorothioate modifications were made. Kinetic analysis, bacterial growth, and β-lactamase activity measurement showed that all the three DNAzymes worked efficiently in vitro and in vivo. A 9 hours bacterial growth inhibition test showed that the inhibition rates of TEM-1 bacteria by Dz1, Dz2, and Dz3 were 27%, 50%, and 29%, respectively. In addition, the inhibition rates of TEM-3 bacteria by those three DNAzymes were found io be 49%, 58%, and 45%, respectively. The current findings suggest that DNAzymes may become potential candidates of alternative inhibitors for bacteria drug-resistance.
基金supported in part by the National Key Basic Research Program of China(No.2002CB513110)Natural Science Foundation of China(No.90606003,No.20505007)+1 种基金Major International(Regional)Joint Research Program of Natural Science Foundation of China(No.20620120107)project supported by Hunan Provincial Natural Science Foundation of China(No.08JJ1002).
文摘Detection of deoxyribozyme （DNAzyme） cleavage process usually needs complex and time-consuming radial labeling, gel electrophoresis and autoradiography. This paper reported an approach to detect DNAzyme cleavage process in real time using a fluorescence probe. The probe was employed as DNAzyme substrate to convert directly the cleavage information into fluorescence signal in real time. Compared with traditional approach, this non-isotope method not only brought a convenient means to monitor the DNAzyme cleavage reaction, but also offered abundant dynamic data for choosing potential gene therapeutic agents. It provides a new tool for DNAzyme research, as well as a new insight into research on human disease diagnosis. Based on this method, 8- 17deoxyribozyme （8-17DNAzyme） against hepatitis C virus RNA （HCV-RNA） was designed and the cleavage process was studied in real time. ？2009 Ke Min Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.
文摘金属离子几乎参与所有生命过程,它们的亚细胞定位与许多生物功能密切相关。亚细胞金属离子的扰动可导致细胞功能受损,并增加代谢相关疾病的风险。最近中国科学院国家纳米科学中心的李乐乐教授基于DNAzyme传感器构建了线粒体中金属离子空间选择性成像的模块化工程,这一成果发表在Journal of The American Chemical Society上。
基金supported by the National Natural Science Foundation of China(22174042 and 22374038)the Natural Science Foundation for Distinguished Young Scholars of Hunan Province(2021JJ10011)the Postgraduate Scientific Research Innovation Project of Hunan Province(CX20220390)。
文摘DNAzyme-based gene therapy faces some challenges including cell penetration,activity limitation,and co-delivery functions.Self-assembled DNA nanomedicine has attracted widespread attention due to its many advantages.It is urgent to develop a universal DNA degradation strategy for precise programmable drug release.Herein,we reported a self-catabolic DNAzyme nanospheres(SCNS),which could simultaneously achieve cell penetration,activity enhancement,and co-delivery functions.The SCNS were assembled through Y-DNA stepwise hybridization with each other,which were then loaded with aptamer(Apt),doxorubicin(Dox),and zinc oxide nanoparticles(ZnO NPs).The acid-triggered dissociation of ZnO NPs leads to the generation of Zn^(2+)ions cofactors for immediately self-catabolic DNAzyme nanospheres.After the disassembly of the SCNS,three types of anticancer treatments would be activated,which include Zn^(2+)involved reactive oxygen species(ROS),Dox-induced chemotherapy,and DNAzyme-based gene therapy.The experimental results show that the nanoplatform(Apt-SCNS-Dox-ZnO)has a good tumor-killing effect and minimal side effects.As a smart self-driven drug delivery nanoplatform,it is anticipated to displace extraordinary potential in biomedicine and bioengineering.
基金financially supported by the National Natural Science Foundation of China(No.82172372)the Opening Research Fund of State Key Laboratory of Digital Medical Engineering(No.2023-M04)。
文摘Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale dimensions.Intelligent DNA machines and networks have been widely used in various fields,including molecular imaging,biosensors,drug delivery,information processing,and logic operations.Encoders serve as crucial components for information compilation and transfer,allowing the conversion of information from diverse application scenarios into a format recognized and applied by DNA circuits.However,there are only a few encoder designs with DNA outputs.Moreover,the molecular priority encoder is hardly designed.In this study,we introduce allosteric DNAzyme-based encoders for information transfer.The design of the allosteric domain and the recognition arm allows the input and output to be independent of each other and freely programmable.The pre-packaged mode design achieves uniformity of baseline dynamics and dynamics controllability.We also integrated non-nucleic acid molecules into the encoder through the aptamer design of the allosteric domain.Furthermore,we developed the 2^(n)-n encoder and the EndoⅣ-assisted priority encoder inspired by immunoglobulin's molecular structure and effector patterns.To our knowledge,the proposed encoder is the first enzyme-free DNA encoder with DNA output,and the priority encoder is the first molecular priority encoder in the DNA reaction network.Our encoders avoid complex operations on a single molecule,and their simple structure facilitates their application in complex DNA circuits and biological scenarios.
